Fair enough, you might say. Londoners had the chance to vote for a fares cut under Ken Livingstone and they voted for Johnson instead. Except that Johnson also promised to reduce the cost of fares during the election. Asked about his policy in a BBC debate, he promised Londoners that he would "bear down on fares" this year. He went on to insist that they would "go down in an honest and sustainable way" if he was re-elected.

Four years earlier Boris made a similar promise to "fight" for lower fares in London, which he complained were "three times the price of the European average".

So how has Johnson's campaign for cheaper transport gone? In every year since he was elected, he has raised fares above inflation. Next January he will make "pay as you go" single bus fares 55% more expensive than they were in 2008.

TfL and the government plan to continue raising fares year after year for the foreseeable future. Despite his promises, Johnson has not fought any of this. Now, you may think that fares need to go up. If you don't use public transport then perhaps you resent subsidising those that do.

You may also think that Johnson's bike hire scheme was ludicrously cheap to begin with. You may believe that it is an unfair travel subsidy for users who are mostly professional men earning more than £50k anyway. But voters should have been able to make this choice at the ballot box. At the very least Johnson should not have pretended that he planned to do the opposite of what he has actually done. Similarly, when Boris sent out his "nine-point plan" to every household in London earlier this year, he should have at least intended to fulfil every point. Instead, Johnson promised that he would employ 1,000 extra police officers – but did he ever have any intention of doing so?

But what has been a mark of Johnson's term in office is his cavalier attitude towards the truth and contempt for public scrutiny. His shameless announcement on fare rises today is just one in a long list of similar examples. So much for his reputation as an honest politician who "tells it like it is".

When his former boss Max Hastings wrote recently that he "would not trust him with my wife or … my wallet", he was writing from painful personal experience. According to Private Eye, Johnson currently owes Hastings an unpaid debt of £1,000. London fare-payers have twice trusted Johnson with their wallets. The rest of Britain should be extremely wary of doing the same with theirs.